The economy is the second largest in the Arab world (after Saudi Arabia), with a gross domestic product (GDP) of $570 billion (AED2.1 trillion) in 2014. The United Arab Emirates has been successfully diversifying its economy,[1] although the UAE remains extremely reliant on oil. With the exception of Dubai, most of the UAE is dependent on oil revenues. Petroleum and natural gas continue to play a central role in the economy, especially in Abu Dhabi. More than 85% of the UAE's economy was based on the oil exports in 2009.[2][3] While Abu Dhabi and other UAE emirates have remained relatively conservative in their approach to diversification, Dubai, which has far smaller oil reserves, was bolder in its diversification policy.[4] In 2011, oil exports accounted for 77% of the UAE's state budget.[5]